In a network field, as a next-generation optical transport technology whose application range is expected to expand, Optical Transport Network (OTN), which can handle packet-based data in an integrated manner, is recommended by ITU-T.
In the OTN, it is possible to handle Time Division Multiplexing (TDM)—based data of Synchronous Optical Network (SONET)/Synchronous Digital Hierarchy (SDH) and the like and packet-based data of Ethernet (registered trademark, hereinafter simply referred to as “LAN”) and the like in an integrated manner.
In the OTN, there is an Optical Channel Data Unit flex (ODUflex) method that can provide a variable band according to demand in order to efficiently transmit packet-based data, which is current main traffic. Further, there is a Hitless Adjustment of ODU flex resizing (HAO) method that realizes a hitless function which stops data error from occurring during normal operation in order to effectively use an optical transmission layer of a transmission apparatus.
Japanese Laid-open Patent Publication No. 2001-177886 and Japanese Laid-open Patent Publication No. 2012-4839 are examples of related art.